Low Exothermic Reaction: Safely Making Thick Epoxy Castings

Why Exothermic Reaction Matters in Deep Pours

Epoxy resins react chemically as they cure, giving off heat in what is known as an exothermic reaction. During thick or large castings, excess heat can quickly build up, leading to warped pieces, internal bubbles, or even thermal cracks. A resin formulated for low exothermic reaction reduces this risk and ensures a more predictable, stable cure.

Choosing the Right Epoxy for Thick Castings

For deep pours—such as river tables or large volume castings—it’s important to use an epoxy resin specifically designed for such applications. “Epoxytable 10-Ten” allows safe casting up to 10 cm in one pour without the overheating commonly seen in general-purpose resins. For castings up to 5 cm, EpoxyTable 5-Five provides similar low-heat benefits tailored to medium-depth projects.

• Always mix by weight as directed (e.g., 100:55 resin to hardener) for optimal results.
• If your project exceeds recommended thickness, consider casting in several layers to better control heat.

When Does Low Exothermic Resin Matter Most?

If your project involves thick slabs, large wooden inlays, or deep embedding, using a low exothermic formulation is essential for achieving both clarity and strength. This approach is especially valuable for river tables, flower preservation, and any pour over 2 cm thick.